The only dvd's/blurays I would consider buying nowadays are TV series that I like: Simpsons, Spongebob, Mad Men, Planet Earth, etc.
One reason is that they are still relatively difficult to download and not always available. Also, the downloads are not as good quality as the physical media so there's still some value in getting a physical copy. In the case of the simpsons, their packaging and presentation is also quite attractive which makes it worth the purchase.